The disclosure is related to a downhole tool for logging a wellbore and in particular to a downhole tool containing a particle detector for detection of particles such as neutrons or gamma-ray or x-ray photons.
Particle detection, such as the detection of neutrons, is used for characterizing the formation around the borehole during exploration, development and production. Measurements may be acquired while drilling or after the well has been drilled, using for instance a wireline tool. Such tools are described in patent applications such as US Re. 36,012.